Commitments and Contingencies - Additional Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) Investment
Commitments And Contingencies [Abstract]
Number of real estate technology investment funds \| Investment	10
Real estate technology investments commitment fund \| $	$ 27.0

Real estate technology investments commitment fund.

No definition available.

Name:	eqr_RealEstateTechnologyInvestmentsCommitmentFund
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant